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-rw-r--r--net/mac80211/agg-tx.c695
1 files changed, 695 insertions, 0 deletions
diff --git a/net/mac80211/agg-tx.c b/net/mac80211/agg-tx.c
new file mode 100644
index 000000000000..947aaaad35d2
--- /dev/null
+++ b/net/mac80211/agg-tx.c
@@ -0,0 +1,695 @@
+/*
+ * HT handling
+ *
+ * Copyright 2003, Jouni Malinen <jkmaline@cc.hut.fi>
+ * Copyright 2002-2005, Instant802 Networks, Inc.
+ * Copyright 2005-2006, Devicescape Software, Inc.
+ * Copyright 2006-2007 Jiri Benc <jbenc@suse.cz>
+ * Copyright 2007, Michael Wu <flamingice@sourmilk.net>
+ * Copyright 2007-2009, Intel Corporation
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <linux/ieee80211.h>
+#include <net/mac80211.h>
+#include "ieee80211_i.h"
+#include "wme.h"
+
+/**
+ * DOC: TX aggregation
+ *
+ * Aggregation on the TX side requires setting the hardware flag
+ * %IEEE80211_HW_AMPDU_AGGREGATION as well as, if present, the @ampdu_queues
+ * hardware parameter to the number of hardware AMPDU queues. If there are no
+ * hardware queues then the driver will (currently) have to do all frame
+ * buffering.
+ *
+ * When TX aggregation is started by some subsystem (usually the rate control
+ * algorithm would be appropriate) by calling the
+ * ieee80211_start_tx_ba_session() function, the driver will be notified via
+ * its @ampdu_action function, with the %IEEE80211_AMPDU_TX_START action.
+ *
+ * In response to that, the driver is later required to call the
+ * ieee80211_start_tx_ba_cb() (or ieee80211_start_tx_ba_cb_irqsafe())
+ * function, which will start the aggregation session.
+ *
+ * Similarly, when the aggregation session is stopped by
+ * ieee80211_stop_tx_ba_session(), the driver's @ampdu_action function will
+ * be called with the action %IEEE80211_AMPDU_TX_STOP. In this case, the
+ * call must not fail, and the driver must later call ieee80211_stop_tx_ba_cb()
+ * (or ieee80211_stop_tx_ba_cb_irqsafe()).
+ */
+
+static void ieee80211_send_addba_request(struct ieee80211_sub_if_data *sdata,
+ const u8 *da, u16 tid,
+ u8 dialog_token, u16 start_seq_num,
+ u16 agg_size, u16 timeout)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sk_buff *skb;
+ struct ieee80211_mgmt *mgmt;
+ u16 capab;
+
+ skb = dev_alloc_skb(sizeof(*mgmt) + local->hw.extra_tx_headroom);
+
+ if (!skb) {
+ printk(KERN_ERR "%s: failed to allocate buffer "
+ "for addba request frame\n", sdata->dev->name);
+ return;
+ }
+ skb_reserve(skb, local->hw.extra_tx_headroom);
+ mgmt = (struct ieee80211_mgmt *) skb_put(skb, 24);
+ memset(mgmt, 0, 24);
+ memcpy(mgmt->da, da, ETH_ALEN);
+ memcpy(mgmt->sa, sdata->dev->dev_addr, ETH_ALEN);
+ if (sdata->vif.type == NL80211_IFTYPE_AP ||
+ sdata->vif.type == NL80211_IFTYPE_AP_VLAN)
+ memcpy(mgmt->bssid, sdata->dev->dev_addr, ETH_ALEN);
+ else if (sdata->vif.type == NL80211_IFTYPE_STATION)
+ memcpy(mgmt->bssid, sdata->u.mgd.bssid, ETH_ALEN);
+
+ mgmt->frame_control = cpu_to_le16(IEEE80211_FTYPE_MGMT |
+ IEEE80211_STYPE_ACTION);
+
+ skb_put(skb, 1 + sizeof(mgmt->u.action.u.addba_req));
+
+ mgmt->u.action.category = WLAN_CATEGORY_BACK;
+ mgmt->u.action.u.addba_req.action_code = WLAN_ACTION_ADDBA_REQ;
+
+ mgmt->u.action.u.addba_req.dialog_token = dialog_token;
+ capab = (u16)(1 << 1); /* bit 1 aggregation policy */
+ capab |= (u16)(tid << 2); /* bit 5:2 TID number */
+ capab |= (u16)(agg_size << 6); /* bit 15:6 max size of aggergation */
+
+ mgmt->u.action.u.addba_req.capab = cpu_to_le16(capab);
+
+ mgmt->u.action.u.addba_req.timeout = cpu_to_le16(timeout);
+ mgmt->u.action.u.addba_req.start_seq_num =
+ cpu_to_le16(start_seq_num << 4);
+
+ ieee80211_tx_skb(sdata, skb, 1);
+}
+
+void ieee80211_send_bar(struct ieee80211_sub_if_data *sdata, u8 *ra, u16 tid, u16 ssn)
+{
+ struct ieee80211_local *local = sdata->local;
+ struct sk_buff *skb;
+ struct ieee80211_bar *bar;
+ u16 bar_control = 0;
+
+ skb = dev_alloc_skb(sizeof(*bar) + local->hw.extra_tx_headroom);
+ if (!skb) {
+ printk(KERN_ERR "%s: failed to allocate buffer for "
+ "bar frame\n", sdata->dev->name);
+ return;
+ }
+ skb_reserve(skb, local->hw.extra_tx_headroom);
+ bar = (struct ieee80211_bar *)skb_put(skb, sizeof(*bar));
+ memset(bar, 0, sizeof(*bar));
+ bar->frame_control = cpu_to_le16(IEEE80211_FTYPE_CTL |
+ IEEE80211_STYPE_BACK_REQ);
+ memcpy(bar->ra, ra, ETH_ALEN);
+ memcpy(bar->ta, sdata->dev->dev_addr, ETH_ALEN);
+ bar_control |= (u16)IEEE80211_BAR_CTRL_ACK_POLICY_NORMAL;
+ bar_control |= (u16)IEEE80211_BAR_CTRL_CBMTID_COMPRESSED_BA;
+ bar_control |= (u16)(tid << 12);
+ bar->control = cpu_to_le16(bar_control);
+ bar->start_seq_num = cpu_to_le16(ssn);
+
+ ieee80211_tx_skb(sdata, skb, 0);
+}
+
+static int ___ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
+ enum ieee80211_back_parties initiator)
+{
+ struct ieee80211_local *local = sta->local;
+ int ret;
+ u8 *state;
+
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+
+ *state = HT_AGG_STATE_REQ_STOP_BA_MSK |
+ (initiator << HT_AGG_STATE_INITIATOR_SHIFT);
+
+ ret = local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_STOP,
+ &sta->sta, tid, NULL);
+
+ /* HW shall not deny going back to legacy */
+ if (WARN_ON(ret)) {
+ *state = HT_AGG_STATE_OPERATIONAL;
+ /*
+ * We may have pending packets get stuck in this case...
+ * Not bothering with a workaround for now.
+ */
+ }
+
+ return ret;
+}
+
+/*
+ * After sending add Block Ack request we activated a timer until
+ * add Block Ack response will arrive from the recipient.
+ * If this timer expires sta_addba_resp_timer_expired will be executed.
+ */
+static void sta_addba_resp_timer_expired(unsigned long data)
+{
+ /* not an elegant detour, but there is no choice as the timer passes
+ * only one argument, and both sta_info and TID are needed, so init
+ * flow in sta_info_create gives the TID as data, while the timer_to_id
+ * array gives the sta through container_of */
+ u16 tid = *(u8 *)data;
+ struct sta_info *sta = container_of((void *)data,
+ struct sta_info, timer_to_tid[tid]);
+ u8 *state;
+
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+
+ /* check if the TID waits for addBA response */
+ spin_lock_bh(&sta->lock);
+ if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
+ spin_unlock_bh(&sta->lock);
+ *state = HT_AGG_STATE_IDLE;
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "timer expired on tid %d but we are not "
+ "expecting addBA response there", tid);
+#endif
+ return;
+ }
+
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "addBA response timer expired on tid %d\n", tid);
+#endif
+
+ ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
+ spin_unlock_bh(&sta->lock);
+}
+
+static inline int ieee80211_ac_from_tid(int tid)
+{
+ return ieee802_1d_to_ac[tid & 7];
+}
+
+int ieee80211_start_tx_ba_session(struct ieee80211_hw *hw, u8 *ra, u16 tid)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct sta_info *sta;
+ struct ieee80211_sub_if_data *sdata;
+ u8 *state;
+ int ret = 0;
+ u16 start_seq_num;
+
+ if (WARN_ON(!local->ops->ampdu_action))
+ return -EINVAL;
+
+ if ((tid >= STA_TID_NUM) || !(hw->flags & IEEE80211_HW_AMPDU_AGGREGATION))
+ return -EINVAL;
+
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Open BA session requested for %pM tid %u\n",
+ ra, tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+
+ rcu_read_lock();
+
+ sta = sta_info_get(local, ra);
+ if (!sta) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Could not find the station\n");
+#endif
+ ret = -ENOENT;
+ goto unlock;
+ }
+
+ /*
+ * The aggregation code is not prepared to handle
+ * anything but STA/AP due to the BSSID handling.
+ * IBSS could work in the code but isn't supported
+ * by drivers or the standard.
+ */
+ if (sta->sdata->vif.type != NL80211_IFTYPE_STATION &&
+ sta->sdata->vif.type != NL80211_IFTYPE_AP_VLAN &&
+ sta->sdata->vif.type != NL80211_IFTYPE_AP) {
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ if (test_sta_flags(sta, WLAN_STA_SUSPEND)) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Suspend in progress. "
+ "Denying BA session request\n");
+#endif
+ ret = -EINVAL;
+ goto unlock;
+ }
+
+ spin_lock_bh(&sta->lock);
+ spin_lock(&local->ampdu_lock);
+
+ sdata = sta->sdata;
+
+ /* we have tried too many times, receiver does not want A-MPDU */
+ if (sta->ampdu_mlme.addba_req_num[tid] > HT_AGG_MAX_RETRIES) {
+ ret = -EBUSY;
+ goto err_unlock_sta;
+ }
+
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+ /* check if the TID is not in aggregation flow already */
+ if (*state != HT_AGG_STATE_IDLE) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "BA request denied - session is not "
+ "idle on tid %u\n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+ ret = -EAGAIN;
+ goto err_unlock_sta;
+ }
+
+ /*
+ * While we're asking the driver about the aggregation,
+ * stop the AC queue so that we don't have to worry
+ * about frames that came in while we were doing that,
+ * which would require us to put them to the AC pending
+ * afterwards which just makes the code more complex.
+ */
+ ieee80211_stop_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
+ /* prepare A-MPDU MLME for Tx aggregation */
+ sta->ampdu_mlme.tid_tx[tid] =
+ kmalloc(sizeof(struct tid_ampdu_tx), GFP_ATOMIC);
+ if (!sta->ampdu_mlme.tid_tx[tid]) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ if (net_ratelimit())
+ printk(KERN_ERR "allocate tx mlme to tid %d failed\n",
+ tid);
+#endif
+ ret = -ENOMEM;
+ goto err_wake_queue;
+ }
+
+ skb_queue_head_init(&sta->ampdu_mlme.tid_tx[tid]->pending);
+
+ /* Tx timer */
+ sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.function =
+ sta_addba_resp_timer_expired;
+ sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.data =
+ (unsigned long)&sta->timer_to_tid[tid];
+ init_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
+
+ /* Ok, the Addba frame hasn't been sent yet, but if the driver calls the
+ * call back right away, it must see that the flow has begun */
+ *state |= HT_ADDBA_REQUESTED_MSK;
+
+ start_seq_num = sta->tid_seq[tid];
+
+ ret = local->ops->ampdu_action(hw, IEEE80211_AMPDU_TX_START,
+ &sta->sta, tid, &start_seq_num);
+
+ if (ret) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "BA request denied - HW unavailable for"
+ " tid %d\n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+ *state = HT_AGG_STATE_IDLE;
+ goto err_free;
+ }
+
+ /* Driver vetoed or OKed, but we can take packets again now */
+ ieee80211_wake_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
+ spin_unlock(&local->ampdu_lock);
+ spin_unlock_bh(&sta->lock);
+
+ /* send an addBA request */
+ sta->ampdu_mlme.dialog_token_allocator++;
+ sta->ampdu_mlme.tid_tx[tid]->dialog_token =
+ sta->ampdu_mlme.dialog_token_allocator;
+ sta->ampdu_mlme.tid_tx[tid]->ssn = start_seq_num;
+
+ ieee80211_send_addba_request(sta->sdata, ra, tid,
+ sta->ampdu_mlme.tid_tx[tid]->dialog_token,
+ sta->ampdu_mlme.tid_tx[tid]->ssn,
+ 0x40, 5000);
+ /* activate the timer for the recipient's addBA response */
+ sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer.expires =
+ jiffies + ADDBA_RESP_INTERVAL;
+ add_timer(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "activated addBA response timer on tid %d\n", tid);
+#endif
+ goto unlock;
+
+ err_free:
+ kfree(sta->ampdu_mlme.tid_tx[tid]);
+ sta->ampdu_mlme.tid_tx[tid] = NULL;
+ err_wake_queue:
+ ieee80211_wake_queue_by_reason(
+ &local->hw, ieee80211_ac_from_tid(tid),
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+ err_unlock_sta:
+ spin_unlock(&local->ampdu_lock);
+ spin_unlock_bh(&sta->lock);
+ unlock:
+ rcu_read_unlock();
+ return ret;
+}
+EXPORT_SYMBOL(ieee80211_start_tx_ba_session);
+
+/*
+ * splice packets from the STA's pending to the local pending,
+ * requires a call to ieee80211_agg_splice_finish and holding
+ * local->ampdu_lock across both calls.
+ */
+static void ieee80211_agg_splice_packets(struct ieee80211_local *local,
+ struct sta_info *sta, u16 tid)
+{
+ unsigned long flags;
+ u16 queue = ieee80211_ac_from_tid(tid);
+
+ ieee80211_stop_queue_by_reason(
+ &local->hw, queue,
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+
+ if (!skb_queue_empty(&sta->ampdu_mlme.tid_tx[tid]->pending)) {
+ spin_lock_irqsave(&local->queue_stop_reason_lock, flags);
+ /* mark queue as pending, it is stopped already */
+ __set_bit(IEEE80211_QUEUE_STOP_REASON_PENDING,
+ &local->queue_stop_reasons[queue]);
+ /* copy over remaining packets */
+ skb_queue_splice_tail_init(
+ &sta->ampdu_mlme.tid_tx[tid]->pending,
+ &local->pending[queue]);
+ spin_unlock_irqrestore(&local->queue_stop_reason_lock, flags);
+ }
+}
+
+static void ieee80211_agg_splice_finish(struct ieee80211_local *local,
+ struct sta_info *sta, u16 tid)
+{
+ u16 queue = ieee80211_ac_from_tid(tid);
+
+ ieee80211_wake_queue_by_reason(
+ &local->hw, queue,
+ IEEE80211_QUEUE_STOP_REASON_AGGREGATION);
+}
+
+/* caller must hold sta->lock */
+static void ieee80211_agg_tx_operational(struct ieee80211_local *local,
+ struct sta_info *sta, u16 tid)
+{
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Aggregation is on for tid %d \n", tid);
+#endif
+
+ spin_lock(&local->ampdu_lock);
+ ieee80211_agg_splice_packets(local, sta, tid);
+ /*
+ * NB: we rely on sta->lock being taken in the TX
+ * processing here when adding to the pending queue,
+ * otherwise we could only change the state of the
+ * session to OPERATIONAL _here_.
+ */
+ ieee80211_agg_splice_finish(local, sta, tid);
+ spin_unlock(&local->ampdu_lock);
+
+ local->ops->ampdu_action(&local->hw, IEEE80211_AMPDU_TX_OPERATIONAL,
+ &sta->sta, tid, NULL);
+}
+
+void ieee80211_start_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u16 tid)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct sta_info *sta;
+ u8 *state;
+
+ if (tid >= STA_TID_NUM) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
+ tid, STA_TID_NUM);
+#endif
+ return;
+ }
+
+ rcu_read_lock();
+ sta = sta_info_get(local, ra);
+ if (!sta) {
+ rcu_read_unlock();
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Could not find station: %pM\n", ra);
+#endif
+ return;
+ }
+
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+ spin_lock_bh(&sta->lock);
+
+ if (WARN_ON(!(*state & HT_ADDBA_REQUESTED_MSK))) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "addBA was not requested yet, state is %d\n",
+ *state);
+#endif
+ spin_unlock_bh(&sta->lock);
+ rcu_read_unlock();
+ return;
+ }
+
+ if (WARN_ON(*state & HT_ADDBA_DRV_READY_MSK))
+ goto out;
+
+ *state |= HT_ADDBA_DRV_READY_MSK;
+
+ if (*state == HT_AGG_STATE_OPERATIONAL)
+ ieee80211_agg_tx_operational(local, sta, tid);
+
+ out:
+ spin_unlock_bh(&sta->lock);
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(ieee80211_start_tx_ba_cb);
+
+void ieee80211_start_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
+ const u8 *ra, u16 tid)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_ra_tid *ra_tid;
+ struct sk_buff *skb = dev_alloc_skb(0);
+
+ if (unlikely(!skb)) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ if (net_ratelimit())
+ printk(KERN_WARNING "%s: Not enough memory, "
+ "dropping start BA session", skb->dev->name);
+#endif
+ return;
+ }
+ ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
+ memcpy(&ra_tid->ra, ra, ETH_ALEN);
+ ra_tid->tid = tid;
+
+ skb->pkt_type = IEEE80211_ADDBA_MSG;
+ skb_queue_tail(&local->skb_queue, skb);
+ tasklet_schedule(&local->tasklet);
+}
+EXPORT_SYMBOL(ieee80211_start_tx_ba_cb_irqsafe);
+
+int __ieee80211_stop_tx_ba_session(struct sta_info *sta, u16 tid,
+ enum ieee80211_back_parties initiator)
+{
+ u8 *state;
+ int ret;
+
+ /* check if the TID is in aggregation */
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+ spin_lock_bh(&sta->lock);
+
+ if (*state != HT_AGG_STATE_OPERATIONAL) {
+ ret = -ENOENT;
+ goto unlock;
+ }
+
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Tx BA session stop requested for %pM tid %u\n",
+ sta->sta.addr, tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+
+ ret = ___ieee80211_stop_tx_ba_session(sta, tid, initiator);
+
+ unlock:
+ spin_unlock_bh(&sta->lock);
+ return ret;
+}
+
+int ieee80211_stop_tx_ba_session(struct ieee80211_hw *hw,
+ u8 *ra, u16 tid,
+ enum ieee80211_back_parties initiator)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct sta_info *sta;
+ int ret = 0;
+
+ if (WARN_ON(!local->ops->ampdu_action))
+ return -EINVAL;
+
+ if (tid >= STA_TID_NUM)
+ return -EINVAL;
+
+ rcu_read_lock();
+ sta = sta_info_get(local, ra);
+ if (!sta) {
+ rcu_read_unlock();
+ return -ENOENT;
+ }
+
+ ret = __ieee80211_stop_tx_ba_session(sta, tid, initiator);
+ rcu_read_unlock();
+ return ret;
+}
+EXPORT_SYMBOL(ieee80211_stop_tx_ba_session);
+
+void ieee80211_stop_tx_ba_cb(struct ieee80211_hw *hw, u8 *ra, u8 tid)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct sta_info *sta;
+ u8 *state;
+
+ if (tid >= STA_TID_NUM) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Bad TID value: tid = %d (>= %d)\n",
+ tid, STA_TID_NUM);
+#endif
+ return;
+ }
+
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Stopping Tx BA session for %pM tid %d\n",
+ ra, tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+
+ rcu_read_lock();
+ sta = sta_info_get(local, ra);
+ if (!sta) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "Could not find station: %pM\n", ra);
+#endif
+ rcu_read_unlock();
+ return;
+ }
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+
+ /* NOTE: no need to use sta->lock in this state check, as
+ * ieee80211_stop_tx_ba_session will let only one stop call to
+ * pass through per sta/tid
+ */
+ if ((*state & HT_AGG_STATE_REQ_STOP_BA_MSK) == 0) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "unexpected callback to A-MPDU stop\n");
+#endif
+ rcu_read_unlock();
+ return;
+ }
+
+ if (*state & HT_AGG_STATE_INITIATOR_MSK)
+ ieee80211_send_delba(sta->sdata, ra, tid,
+ WLAN_BACK_INITIATOR, WLAN_REASON_QSTA_NOT_USE);
+
+ spin_lock_bh(&sta->lock);
+ spin_lock(&local->ampdu_lock);
+
+ ieee80211_agg_splice_packets(local, sta, tid);
+
+ *state = HT_AGG_STATE_IDLE;
+ /* from now on packets are no longer put onto sta->pending */
+ sta->ampdu_mlme.addba_req_num[tid] = 0;
+ kfree(sta->ampdu_mlme.tid_tx[tid]);
+ sta->ampdu_mlme.tid_tx[tid] = NULL;
+
+ ieee80211_agg_splice_finish(local, sta, tid);
+
+ spin_unlock(&local->ampdu_lock);
+ spin_unlock_bh(&sta->lock);
+
+ rcu_read_unlock();
+}
+EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb);
+
+void ieee80211_stop_tx_ba_cb_irqsafe(struct ieee80211_hw *hw,
+ const u8 *ra, u16 tid)
+{
+ struct ieee80211_local *local = hw_to_local(hw);
+ struct ieee80211_ra_tid *ra_tid;
+ struct sk_buff *skb = dev_alloc_skb(0);
+
+ if (unlikely(!skb)) {
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ if (net_ratelimit())
+ printk(KERN_WARNING "%s: Not enough memory, "
+ "dropping stop BA session", skb->dev->name);
+#endif
+ return;
+ }
+ ra_tid = (struct ieee80211_ra_tid *) &skb->cb;
+ memcpy(&ra_tid->ra, ra, ETH_ALEN);
+ ra_tid->tid = tid;
+
+ skb->pkt_type = IEEE80211_DELBA_MSG;
+ skb_queue_tail(&local->skb_queue, skb);
+ tasklet_schedule(&local->tasklet);
+}
+EXPORT_SYMBOL(ieee80211_stop_tx_ba_cb_irqsafe);
+
+
+void ieee80211_process_addba_resp(struct ieee80211_local *local,
+ struct sta_info *sta,
+ struct ieee80211_mgmt *mgmt,
+ size_t len)
+{
+ u16 capab, tid;
+ u8 *state;
+
+ capab = le16_to_cpu(mgmt->u.action.u.addba_resp.capab);
+ tid = (capab & IEEE80211_ADDBA_PARAM_TID_MASK) >> 2;
+
+ state = &sta->ampdu_mlme.tid_state_tx[tid];
+
+ spin_lock_bh(&sta->lock);
+
+ if (!(*state & HT_ADDBA_REQUESTED_MSK)) {
+ spin_unlock_bh(&sta->lock);
+ return;
+ }
+
+ if (mgmt->u.action.u.addba_resp.dialog_token !=
+ sta->ampdu_mlme.tid_tx[tid]->dialog_token) {
+ spin_unlock_bh(&sta->lock);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "wrong addBA response token, tid %d\n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+ return;
+ }
+
+ del_timer_sync(&sta->ampdu_mlme.tid_tx[tid]->addba_resp_timer);
+#ifdef CONFIG_MAC80211_HT_DEBUG
+ printk(KERN_DEBUG "switched off addBA timer for tid %d \n", tid);
+#endif /* CONFIG_MAC80211_HT_DEBUG */
+ if (le16_to_cpu(mgmt->u.action.u.addba_resp.status)
+ == WLAN_STATUS_SUCCESS) {
+ u8 curstate = *state;
+
+ *state |= HT_ADDBA_RECEIVED_MSK;
+
+ if (*state != curstate && *state == HT_AGG_STATE_OPERATIONAL)
+ ieee80211_agg_tx_operational(local, sta, tid);
+
+ sta->ampdu_mlme.addba_req_num[tid] = 0;
+ } else {
+ sta->ampdu_mlme.addba_req_num[tid]++;
+ ___ieee80211_stop_tx_ba_session(sta, tid, WLAN_BACK_INITIATOR);
+ }
+ spin_unlock_bh(&sta->lock);
+}